Quarterly report pursuant to Section 13 or 15(d)

Supplemental Cash Flow Information (Details)

v3.8.0.1
Supplemental Cash Flow Information (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Cash paid during the period for:    
Income taxes $ 4,433 $ 9,265
Interest 16,557 21,576
Non-cash investing activity:    
Capital expenditures acquired on account but unpaid as of the period end $ 10,680 $ 8,599